Google just launched the developer preview for its upcoming version of Android last week, and some tinkerers have already put the new software to the test.

Ron Amadeo at Ars Technica ran the website's battery test on a phone running Android L to see just how well Google's new battery saver initiative works in practice.

Android L comes with a host of new features, mostly backend enhancements, aimed at extending general battery life across Android devices called Project Volta.

An improved battery stat tracker called Battery Historian and new application programming interfaces designed to cut down on wasted effort are part of Google's plan to boost battery life.

To run a battery test that was as accurate as possible, Amadao flashed a Nexus 5 to Android 4.4.4, the latest version of KitKat, and ran Ars Technica's battery test. To ensure consistency, he also flashed the same device to run Android L and ran the exact same test. Think of flashing as a sort of reprogramming the phone's software.

Amadao found that the Nexus 5 lasted for 471 minutes running Android L compared to 345 minutes while running KitKat.

That equals about 7.8 hours on L versus 5.7 hours running KitKat. According to Amadao, that's about a 36% increase in general battery life. The battery test involved keeping the screen on while connected to Wi-Fi and refreshing web pages every 15 seconds until the battery completely drained.

We expect to learn more about Android L when it officially rolls out to consumers later this year.